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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

27301 results found.

  1. Swift GRB 230805B: Global MASTER-Net observations report
  2. GRB 230805B: Swift detection of a burst
  3. GRB 230805A: Fermi GBM Final Real-time Localization
  4. GRB 230802A: Fermi GBM observation
  5. GRB 230802A: Swift-BAT refined analysis
  6. GRB 230804A: Fermi GBM Final Real-time Localization
  7. Fermi trigger No 712798043: Global MASTER-Net observations report
  8. GRB 230802A: Swift/UVOT Upper Limits
  9. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  10. Fermi trigger No 712718833: Global MASTER-Net observations report
  11. GRB 230803A: Fermi GBM Final Real-time Localization
  12. Fermi trigger No 712713532: Global MASTER-Net observations report
  13. Fermi trigger No 712651827: Global MASTER-Net observations report
  14. GRB 230802B: Fermi GBM Final Localization
  15. Swift GRB 230802A: Global MASTER-Net observations report
  16. GRB 230802A: BOOTES-5/JGT optical upper limit
  17. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  18. GRB 230802A: Swift-XRT refined Analysis
  19. LIGO/Virgo/KAGRA S230802aq: Coverage and upper limits from MAXI/GSC observations
  20. GRB 230802A: Swift detection of a burst
  21. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  22. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  23. LIGO/Virgo/KAGRA S230731an: not observable by Fermi-GBM
  24. GRB 230731A: Fermi GBM Final Real-time Localization
  25. LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations
  26. Fermi trigger No 712390645: Global MASTER-Net observations report
  27. GRB 230728A: Swift-BAT refined analysis
  28. GRB 230723B: Swift-BAT refined analysis
  29. Fermi trigger No 712306969: Global MASTER-Net observations report
  30. GRB 230728A: BOOTES-1 optical upper limit
  31. GRB 230728A: Fermi GBM Observation
  32. GRB 230728A: LCOGT Optical Upper Limit
  33. GRB 230728A: Swift/UVOT Upper Limits
  34. GRB 230728A: Swift-XRT refined Analysis
  35. GRB 230728A: NOT optical observations and possible host galaxy
  36. GRB 230728A: Swift detection of a burst
  37. Swift GRB230728.12: Global MASTER-Net observations report
  38. GRB 230727A: Swift/BAT-GUANO detection of a burst
  39. Fermi trigger No 712143685: Global MASTER-Net observations report
  40. GRB 230727A: Fermi GBM Final Real-time Localization
  41. Integral GRB230726.26: Global MASTER-Net observations report
  42. Konus-Wind detection of GRB 230723A
  43. LIGO/Virgo/KAGRA S230726b: one counterpart neutrino candidate from IceCube neutrino searches
  44. IBAS trigger number 10337: not a real GRB
  45. Integral GRB230725.99: Global MASTER-Net observations report
  46. IceCube Alert 230725.90: Global MASTER-Net observations report
  47. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  48. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  49. GRB 230725B: Fermi GBM Final Real-time Localization
  50. GRB 230725A: Fermi GBM Final Real-time Localization
  51. GRB 230723B: Leavitt Observatory upper limit
  52. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  53. GRB 230723B: Montarrenti Observatory upper limit
  54. GRB 230723B: Bassano Bresciano Observatory upper limit
  55. GRB 230723B: Fermi GBM observation
  56. GRB 230723B: Swift-XRT refined Analysis
  57. GRB 230723B: non-detections from Observatoire de Haute-Provence
  58. IceCube Alert 230724.08: Global MASTER-Net observations report
  59. Fermi trigger No 711853834: Global MASTER-Net observations report
  60. GRB 230724A: Fermi GBM Final Real-time Localization
  61. Fermi trigger No 711805358: Global MASTER-Net observations report
  62. GRB 230723B: Swift/UVOT Upper Limits
  63. Swift GRB 230723B: Global MASTER-Net observations report
  64. Swift-XRT position for GRB 230723B
  65. GRB 230723B: Swift-XRT observations
  66. GRB 230723B: Swift detection of a burst
  67. Fermi GRB 230723A: Global MASTER-Net observations report
  68. GRB 230723A: Fermi GBM Final Real-time Localization
  69. Swift GRB230720.30: Global MASTER-Net observations report
  70. IPN triangulation of GRB 230715D
  71. Swift Trigger 1180063 is not a GRB
  72. Swift Trigger 1180060 is not a GRB
  73. Swift Trigger 1180055 is not a GRB
  74. GRB 230718A: Final Localization Correction
  75. GRB 230718A: Fermi GBM Final Real-time Localization
  76. Fermi Gamma-ray Burst Monitor trigger 711329677/230717982 is not a GRB
  77. IPN triangulation of GRB 230712C (short)
  78. IPN triangulation of GRB 230712A (short)
  79. GRB 230717A: Fermi GBM Final Real-time Localization
  80. LIGO/Virgo/KAGRA S230715bw: Retraction of GW compact binary merger candidate
  81. Fermi trigger No 711088412: Global MASTER-Net observations report
  82. GRB 230715A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 230713A: Global MASTER-Net observations report
  84. IceCube-230707A : MAXI upper limit and NICER follow-up observation of Swift J1753.5-0127
  85. GRB 230713A: Fermi GBM Final Real-time Localization
  86. GRB 230709B: CALET Gamma-Ray Burst Monitor detection
  87. GRB 230703A: CALET Gamma-Ray Burst Monitor detection
  88. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  89. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  90. GRB 230712B: Fermi GBM Final Localization
  91. LIGO/Virgo/KAGRA S230712a: Retraction of GW compact binary merger candidate
  92. GRB 230712A: Fermi GBM Final Real-time Localization
  93. Fermi trigger No 710741042: Global MASTER-Net observations report
  94. GRB 230709C: Fermi GBM Detection
  95. GRB 230709C: Fermi GBM Final Localization
  96. GRB 230707B: Fermi GBM Observation
  97. GRB 230710A: Fermi GBM Final Real-time Localization
  98. IceCube-230707A: No candidates detected by Swift-XRT
  99. Swift Trigger 1178410 is not an astrophysical event
  100. GRB 230707B: CALET Gamma-Ray Burst Monitor detection

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